You’ve probably seen the video we did a while back on the seed starting and transplanting process that we use in our greenhouse. In our greenhouse we use traditional soil, peat, coco coir, etc. But many of you are concerned with solids build up in your indoor systems. (Read more: This is a real concern, especially if your don’t have really aggressive aeration! And since we think that indoor systems should be as simple and low-maintenance as possible, we’re going to show you a few seed starting options for indoor growers.

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Music By: Blue Ducks
Track Title: “Four, Floss, Five, Six”

Types of Plugs for Starting Seeds in Commercial Vertical Hydroponics

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  • Mitchell Fite

    rockwool does break down, fibers are so thin that once it gets physically broken down (torn, smooshed, pulverized, etc) enough that its pieces are small enough, it goes through the same process as leaf litter. its slower than leaves, but it really will distinigrate. add it to potting soil or compost! it is awesome additive! break it apart by rolling between the fingers(AFTER WETTING THOROUGHLY!) and toss it in

  • areaSixTwelve

    Rock's not particularly biodegradable either, right? I understand your concern about landfills filling up more quickly, but it's not like adding newly permanent chemical structures to the ecosystem, like we do so often with petroleum-based plastics. Or am I missing something?

  • Raven Moon

    Im just learning about aquaponics and this is very helpful. Traditional gardening is a little difficult fro me to keep up with. Setting up a system has been a learning process. Im still not set up and growing but I will be soon. Thank you for the lessons

  • Frank De Block-Burij

    hello, you refer to the video on the seed starting and transplanting process. Could you pinpoint this video (there are so many, thanks)

  • Richard Taylor

    I was using rock wool plugs, but recently started switching over to the Rapid Rooter brand of flexible choir plugs. They are much simpler to use, and come PH balanced. No need to pre-soak them in a PH 5 water prior to planting as with rock wool. For people new to this, that alone could be the difference between success/failure and simplicity in planting. Most come pre-moistened, so you simply drop in the seed, place it in a tray, and continue with normal propagation methods.

    Yes, they are more expensive. A bag of 100 at the local hydro store was $26.00. You can find them cheaper in bulk online, but you may want to start with a small bag to see if they are suitable for what you need.

    For some of the finer rooted plants, I have found better initial growth in the choir flexi plugs than rockwool. It's substrate expands easily for root penetration, and I see the increased length of the plug as being beneficial to 'stabilize' the plant prior to transplanting as well.

    Also, i find less algae growth on the medium if placed into direct sunlight than rockwool.

    I will be experimenting with both mediums in the new propagation chamber soon, thanks to the recent video here about their use. Thanks for that info!

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